Climate Warming Favoring Sublimation on a Westerlies-Controlled Glacier of Tibetan Plateau

During the past few decades, the climate over the entire TP changed obviously with general warming and the decreasing trends in wind speed and air humidity. As an important hydrological process of mass losses on the TP glaciers, especially during the cold period, sublimation may be influenced deeply by the climate changes. Therefore, it is imperative to identify the crucial factors controlling and limiting glacier sublimation and analyze its possible changes in the future. The sublimation on a flat-topped glacier of TP was found to be more intense in spring (0.41 mm d-1) and autumn (0.34 mm d-1) and weak in winter (0.27 mm d-1) and summer (0.16 mm d-1). At yearly scale, sublimation was most sensitive to the surface temperature, followed by air temperature and humidity, and was relatively insensitive to wind speed. However, the main influencing factor was air humidity during summer, showing a strong inhibition on sublimation. The very low surface temperature was the most crucial variable limiting winter sublimation with the highest sensitivity coefficient than other variables. Current sublimation was also found to be more sensitive to the increasing temperature than the decreased air humidity and wind speed. If the climate trends continue, and the glacier climate has the relatively consistent change trend with that of entire TP, glacier sublimation will be more likely to increase, especially during winter. The climate warming trend in the TP has been found to be more sensitive and accelerated since the end of last century. Our study found that, on the August-one glacier, the very high air humidity and low surface temperature were the most crucial variables limiting summer and winter sublimation, respectively. The glacier sublimation was significantly more sensitive to the surface and air temperature than air humidity and wind speed at yearly scale. With a general warming and the decreasing trends in wind speed and air humidity over the entire TP, sublimation will be more likely to increase as the temperature rises on this glacier, especially during winter. Very high air humidity and low surface temperature were the most crucial variables limiting summer and winter sublimation, respectivelyGlacier sublimation was significantly more sensitive to the surface and air temperature than air humidity and wind speed at yearly scaleUnder climate warming, sublimation will be more likely to increase as the temperature rises on this glacier, especially during winter